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' Aug. 11, 1959 A. L. CRESCI 2,399,172

ELEVATING MECHANISM FOR TRUCK BODIES Filed May 13, 1953 5 Sheets-Sheet 1 ANTHONY 1.. 017556! INVENTOR ATTORNEYS A. L. CRESCI ELEVATING MECHANISM FOR ,TRUCK BODIES Aug. 11, 1959 3 Sheets-Sheet 2 Filed May 13, 1958 mmo/w 1.. GRESO/ BY 4% 1% MW ATTORNEYS Aug. 11, 1959 x A. L. CRESCI ELEVATING MECHANISM FOR TRUCK BODIES 3 Sheets-Sheet 3 Filed May 13, 1958 ANTHONY L. misc! BY All; s M

ATTORNEYS ELEVATING MECM FOR TRUCK BODIES Anthony L. Cresci, Vineland, NJ. Application May 13, 1958, Serial No. 734,913

8 Claims. (Cl. 254-8) The present invention relates to mechanism for elevating a truck body a substantial distance above its chassis and is similar in some respects to the arrangement illustrated in the patent to Cresci 2,706,102, wherein a pair of crossed lever arms are pivotally connected intermediate their ends and these levers have pivotal connections to the body and chassis respectively.

One of the objects of the invention is to overcome initial resistance to elevation of the body by providing in combination with a hydraulic ram a novel form of cam mechanism which acts to raise the body in the preliminary lifting stages.

Another object of the invention is to combine the hydraulic ram with the cam in such a manner that, when the cam has raised the levers some distance beyond dead center of their pivotal connection, the ram acts directly on the levers to complete the maximum elevation of the truck body.

Other and obvious objects of the inventionpwill be apparent from the following description thereof taken with the accompanying drawings in Which Fig. 1 is a side elevation of the mechanism forming a preferred embodiment of the invention;

Fig. 2 is an end view of the mechanism shown in Fig. 1;

Fig. 3 is a side view of the levers and cam in one position thereof;

Fig. 4 is a view similar to Fig. 3 with the levers in collapsed or lowermost position;

Fig. 5 is a partial perspective of the means for guiding the lower ends of the levers; and

Fig. 6 is an exploded perspective of parts of the mechanism illustrated in Fig. 1.

In the drawings, the chassis frame is shown at 10 and the truck body frame at 11. Connecting the body to the chassis are a pair of outside levers 12 and a pair of inside levers 13, the levers being pivotally connected by a cross shaft 14. Levers 12 are pivotally connected to the chassis frame at 15, While levers 13 are pivotally connected to the body frame at 16. The upper end of each of the levers 12 carries a roller 17 constrained to move in a straight line in channel tracks 18 forming part of the body frame. The lower end of each of the levers 13 carries a pair of rollers 19 constrained to move in channel tracks 21 forming part of the body frame.

Pivoted on cross shaft 14 are cam members 22 the upper end of each of which is pivotally connected by a cross member 27 to the movable cylinder of a hydraulic ram 23, the latter being pivoted to the chassis frame at 24. Each cam is provided with a free elongated tail portion 25 which is adapted to ride on a roller 26 journaled in the chassis frame at each side thereof when moving from its lowermost position, as shown in Fig. 4, and during the initial stage of elevation to the position illustrated in Fig. 3. When the body is in its lowermost position, as seen in Fig. 4, the body frame rests directly on the chassis frame. At this time the ram is confined entirely within the combined heights of the body and chassis flames which in the present construction is approximately fifteen inches. Thus it is possible not only to reduce this combined height to a minimum, but the pivotal connection of the levers may be lowered to a point just above its dead center.

It will be seen from Fig. 4 that the angle of the hydraulic ram with respect to the horizontal is such that its connection 27 with cam 22 is above the pivotal connection -14 of the levers. The cam 22 also has a rounded portion or land 28 on the underside thereof which is concentric With the cross shaft 14. As fluid under pressure, supplied by pump 29, forces cylinder 23 rearwardly, the cam portion 28 rides over roller 26 and initiates the first stage of elevation, thus raising the pivot of the lever linkage. At the same time the upper end of the cam, that is that end pivotally connected to the ram cylinder, moves in a clockwise direction about shaft 14 as seen in Fig. 3. The tail portion 25 of the cam meanwhile engages the roller 26 to resist this rotation of the cam, so that there is no abrupt movement of the upper end of the cam when the rounded portion 28 rises out of contact with roller 26. The cam member is so designed that the tail portion thereof is sufliciently long that it continues to engage roller 26 until the cross bar 27 is substantially in vertical alignment with cross shaft 14. Thus the ram is permitted continuously to exert sufiicient force to the linkage further to raise the body. The upper end of each cam at this time engages a stop member '30 protruding from each of levers 13 so that the thrust of the ram is now exerted directly against levers 13 and through their pivotal connection with levers 12 to the latter through the final stages of body lift. It is to be noted that the pivotal connection 27 between the cam member and the ram is above the pivotal connection 14 regardless of the position of the cam. In order to relieve the ram of the weight of the fully raised truck body, the linkage may be locked in the position shown in Fig. l by pins 31 inserted in suitable apertures in the tracks 21. These pins are engageable by rollers 19 to prevent the latter from moving toward the collapsed position of the lever linkage.

When the truck body is to be lowered, the fluid in the ram is released through suitable valve mechanism, the Weight of the body being sufficient to force the fluid out of the ram. As the levers reach the position shown in Fig. 3, the upper end portion of cam 22 moves out of contact with stop 30 and, were it not for the resistance exerted by the tail portion of the cam riding on roller 26, the linkage would lower relatively rapidly. The cam thus acts as a buifer to rapid fluctuations in the final stages of the lowering operation. The cams are so dimensioned that they, as well as the ram, are entirely confined within the combined heights of the chassis and body frames when the body rests directly on the chassis. Thus in this latter position no parts of the ram or cams protrude above the body frame or below the chassis frame.

While a preferred form of the invention has been illuslustrated and described, it is obvious that such changes as fall within the scope of the claims are permissible.

What is claimed is:

l. A load carrying vehicle including a chassis frame, a body frame adapted to rest on said chassis frame, elevating mechanism for the body frame comprising a pair of arms pivoted to each other intermediate the ends of said arms, each of said arms comprising a rigid one-piece member, one end of one of said arms having a pivotal connection with said chassis frame, one end of the other of said arms having a pivotal connection with said body frame, said connections being in vertical alignment, said chassis frame and said body frame each having a track thereon, a roller mounted on the other end of said one arm engaging the track on said body frame, a roller mounted on the other end of said other arm engaging the track on said chassis frame, a cam member pivoted intermediate its ends to the other of said arms, a roller journaled on said chassis frame, power means connected to one end of said cam member, a land on said earn member'engageablewith said journaled roller to lift said'body frame: from itsrest-' ing position'on the chassis frame in the initial sta'ges of elevation, the free end of said' cam membercomprising an elongated portion engagingsaid journaled roller during a subsequent period of elevation of the body frame, and an abutment on said other arm engageable by said one end of said cam to receive the direct thrust of said power means during the final stages of elevation'of the body frame.

2. A load carrying vehicle as defined in claim 1 in which the cammember is pivoted on the pivotal connection betweensaid arms.

3. A load carrying vehicle as defined in claim Z'in which the pivotal connection between the cam member and said power means is in a plane spaced above the pivotal connection between said arms in all positions of the cam member.

4.- A load carrying vehicle as defined in claim 3 in which the power means comprises a fluid operated rain and in which said ram, cam, and roller are confined within the space defined by the plane of the upper face of the body frame and the plane of the lower face of the chassis frame when said upper frame is resting on said chassis frame.

5. A load carrying vehicle as defined in claim 3 in which said land is on the underside of said member.

6. A load carrying vehicle as defined in claim 5 in which the surface of said land is concentric with the pivotal connection between said power means and said member.

7. A load carrying vehicle as defined in claim 6 in which said journaled roller is in engagement with said land when said body frame is in resting position on said chassis frame.

8. A load carrying vehicle as defined in claim 1 in which said elongated portion is substantially straight and remains in engagement with said journaled roller only until said cam member engages said abutment.

References Cited in the'file of this patent UNITED STATES PATENTS 2,471,901 Ross May 31 1949 2,476,380 Manke July 19, 1949 2,706,102 Cresci Apr. 12, 1955 

